激光石墨化沥青基碳纤维的力学性能研究

Mechanical properties of laser graphitized pitch-based carbon fiber

为提升沥青基碳纤维的力学性能,采用自制的激光超高温石墨化装置对中间相沥青基碳纤维进行石墨化处理。通过改变实验过程中的激光功率、牵伸力及碳纤维直径等3个因素制备了多组样品,研究了沥青基碳纤维拉伸强度随温度的变化规律,并分析了石墨化过程中牵伸力及碳纤维直径对其力学性能的影响。结果表明:沥青基碳纤维石墨化能承受的最大激光功率为360 W,对应的温度约为3050℃,在此条件下处理得到的碳纤维拉伸强度由1.0 GPa提升至2.5 GPa;在碳纤维的承受范围内,其力学性能随着温度、牵伸力的增加而提高;直径较小的碳纤维力学性能提升更大。

In an attempt to improve the mechanical properties of pitch-based carbon fibers,graphitization of mesophase pitch-based carbon fibers using a custom-built ultra-high temperature laser graphitization device has been investigated.Multiple sets of samples were prepared by changing the laser power,drafting force and carbon fiber diameter during the experiment.The variation in tensile strength of pitch-based carbon fibers as a function of temperature was studied,and the influence of the drawing force and carbon fiber diameter on mechanical properties during graphitization was analyzed.The results show that pitch-based carbon fibers can withstand a maximum laser power of 360 W during graphitization,under which conditions the tensile strength of the resulting material can be increased from 1.0 GPa to 2.5 GPa.In the carbon fiber tolerance range,the mechanical properties of the materials increase with increasing temperature and drafting force.In particular,the mechanical properties of carbon fibers with smaller diameter increase most significantly.